scholarly journals PROFESSIONAL RISKS TO HEALTH OF THE PERSONNEL OF EXIT BRIGADES OF SERVICE OF THE FIRST HELP

2021 ◽  
Vol 21 (4) ◽  
pp. 17-23
Author(s):  
V. O. Krasovskij ◽  
L. M. Karamova ◽  
G. R. Basharova

Clause analyzes the reasons of professional risks for health of the personnel of exit brigades of the first help. Clinical and hygienic researches in regional substation of a megacity have shown that in labour activity of these workers it is necessary to consider as leading professional harm action of transport vibration. The given circumstance and other reasons provide professional risks of development of illnesses of cardiovascular, bone-muscular system, a gastroenteric path. The interdepartmental complex of actions on improvement of operating conditions of the exit personnel is offered.

2021 ◽  
Vol 11 (1) ◽  
pp. 896-906
Author(s):  
David Strnad ◽  
Gabriel Fedorko ◽  
Juraj Dribnak

Abstract Intralogistics contributes significantly to the proper functioning of business processes. When designing and solving intralogistics systems, it is necessary to take into account the specific conditions in the given enterprise. The technical design, as well as the composition of the trolleys in the design of the transport system, must respect the specificities of the goods transported as well as shelf life and quantity. The study presents, for example, the implementation of a tugger train into an intercompany system with a solution procedure that is adapted to specific operating conditions and ensures the smooth functioning of the supply process. It is a principle based on the use of a simulation model. During its creation, three original sequences were developed in the programming language SimTalk. Their application decreases the use of blocks from the simulation program by up to 65% and it was possible to model more detailed processes that would not be possible in terms of functionality by using classical blocks. Fifteen directions of the language SimTalk were applied in their creation. Two variables of the type Integer, two variables of the type Object, and one variable of the type Real were defined.


2019 ◽  
Author(s):  
Mohadeseh Seyednezhad ◽  
Hamidreza Najafi

Abstract An energy and economic analysis of a novel hybrid photovoltaic-thermoelectric (PV-TEC) system for building cooling applications is presented. It is considered that the roof is constructed from building integrated photovoltaic panels (BIPV) and thermoelectric (TEC) cooling modules are installed on top of the ceiling. The TEC modules are supplied by the PV panels, reducing the ceiling temperature and therefore maintaining a comfortable temperature for the occupants. A mathematical model is developed in MATLAB to simulate the performance of the hybrid PV-TEC system. A building energy model is also developed in eQuest to simulate the performance of a case study office building in Melbourne, FL. The hourly cooling demands are evaluated from the building model, and the PV-TEC system is sized to satisfy the cooling loads accordingly. The total annual energy consumption of the PV-TEC system is then calculated for various operating conditions according to the given characteristics for the selected TEC module and the required number of PV panels to supply the thermoelectric system with adequate electricity is evaluated. The cost of the system and associated savings are determined and discussed in detail. The results show that the proposed system is capable of maintaining the set point temperature for occupants’ comfort. The initial estimated cost of the hybrid PV-TEC system is found significantly higher than conventional air conditioning systems. However, the attractive features of the proposed system including high controllability and maintenance free operation as well as no need to refrigerant or major moving part are some of the aspects that are promising for building cooling applications.


2017 ◽  
Vol 170 (3) ◽  
pp. 66-72
Author(s):  
Jerzy MERKISZ ◽  
Łukasz RYMANIAK

The article discusses the possibility of determining the environmental indicators for vehicles of different categories in relation to CO2 emissions. These are called toxicity indicators because they concern the compounds: CO, THC and NOx. Three Euro V compliant vehicles with different propulsion systems types were used for the study: a 0.9 dm3 urban passenger car with a SI engine and a start-stop system, a 2.5 dm3 off-road vehicle with a CI engine, and a city bus with a hybrid drive system in series configuration and a CI engine with a displacement of 6.7 dm3. Measurements were made in actual operating conditions in the Poznan agglomeration using a portable emissions measurement system (PEMS). The paper presents the characteristics of the operating time shares of vehicles and propulsion systems as well as CO2 emissions depending on the engine load and crankshaft rotational speed for individual vehicles. The determined toxicity indicators allowed to indicate their usefulness, to make comparisons between tested vehicles, and to identify directions for further work on the application and interpretation of these indicators.


Author(s):  
V. Tverdomed

The traditional structure of the upper structure of the track on the main railways of Ukraine in curved sections with a radius of less than 350 m is a link structure of the track with wooden sleepers. This track design is not rational under current operating conditions. The use of a more advanced jointless track design in curves with a radius of less than 350 m is limited primarily by the condition of ensuring the transverse stability of the rail-sleeper lattice. To be able to expand the use of jointless track construction in curved sections with a radius of less than 350 m, it is necessary to know the values of the transverse forces of interaction of the structures of the upper track structure with the moving carriage. Knowing the forces of interaction, it is possible to estimate by what value the transverse stability of the rail-sleeper lattice will be provided and to make constructive decisions on its increase. The method of determination of transverse horizontal forces of interaction of track and moving carriage in curves of radius less than 350 m taking into account quasi-static compressive forces in a train is given. The reasons for these forces are related to the presence of eccentricity of the autoclutch shank in the horizontal and vertical planes. Theoretical calculations of horizontal transverse forces of interaction are carried out according to the given technique and coefficients of stability of a rail-sleeper lattice in curved sites are defined. The main conclusions concerning the possibility of operation of the jointless track structure in curved sections with a radius of 350 m and less are made.


Studia Humana ◽  
2020 ◽  
Vol 9 (3-4) ◽  
pp. 120-130
Author(s):  
Tomasz Jarmużek ◽  
Mateusz Klonowski ◽  
Rafał Palczewski

AbstractIn this paper, we indicate how Jan Woleński’s non-linguistic concept of the norm allows us to clarify the deontic relationship between sentences and the given normative system. A relationship of this kind constitutes a component of the metalogic of relating deontic logic, which subjects the logical value of the deontic sentence to the logical value of the constituent sentence and its relationship with a given normative system in the accessible possible worlds.


Author(s):  
Gleb L. Kotkin ◽  
Valeriy G. Serbo

If the potential energy is independent of time, the energy of the system remains constant during the motion of a closed system. A system with one degree of freedom allows for the determination of the law of motion in quadrature. In this chapter, the authors consider motion of the particles in the one-dimensional fields. They discuss also how the law and the period of a particle moving in the potential field change due to adding to the given field a small correction.


Author(s):  
Chao Huo ◽  
Nestor Gonzalez Diez ◽  
Arvind Gangoli Rao

The Advisory Council for Aeronautics Research in Europe (ACARE) has set an ambitious array of objectives to be accomplished by 2050. It is often claimed that complying with those targets will not require evolution but, rather, revolution. If the growth in aviation has to be sustained in the future then we must come up with radical aircraft and engine configurations which can meet the demands of future aviation. The contra-rotating fan is one such system which can play an important role in the future engine configurations, such as the hybrid engine configuration that is being investigated in the EU cofounded AHEAD project. In order to design a CRF system, a 1-D code has been developed based on the inverse Blade Element Method (BEM) to design a contra rotating fan. The CRF design obtained from this methodology is then analyzed with a full 3D RANS simulation. The numerical analysis revealed that the performance of the first rotor satisfies with the given design requirements in terms of both pressure ratio and isentropic efficiency, thus proving the efficacy of using the 1-D code for designing the CRF. However, the performance of the rear rotor does not reach the design demands. It was observed that there is a strong flow separation around the root and a strong normal shock in the blade passage near the tip. It was found that there is a great difference between the blade metal inlet angles and the relative flow inlet angles near the root of the rear rotor. One of the main reasons for this is the calculation of the axial velocity depending on the vortex design and the resolution of the radial equilibrium. Based on the CFD simulations, the design code could be further modified to improve the design of CRF.


2012 ◽  
Vol 134 (6) ◽  
Author(s):  
R. Schnell ◽  
J. Yin ◽  
C. Voss ◽  
E. Nicke

The present study demonstrates the aerodynamic and acoustic optimization potential of a counter rotating open rotor. The objective was to maximize the propeller efficiency at top of climb conditions and to minimize the noise emission at takeoff while fulfilling the given thrust specifications at two operating conditions (takeoff and top of climb) considered. Both objectives were successfully met by applying an efficient multi-objective optimization procedure in combination with a 3D RANS method. The acoustic evaluation was carried out with a coupled U-RANS and an analytic far field prediction method based on an integral Ffowcs Williams-Hawkings approach. This first part of the paper deals with the application of DLR’s CFD method TRACE to counter rotating open rotors. This study features the choice and placement of boundary conditions, resolution requirements, and a corresponding meshing strategy. The aerodynamic performance in terms of thrust, torque, and efficiency was evaluated based on steady state calculations with a mixing plane placed in between both rotors, which allowed for an efficient and reliable evaluation of the performance, in particular, within the automatic optimization. The aerodynamic optimization was carried by the application of AutoOpti, a multi-objective optimization procedure based on an evolutionary algorithm, which also was developed at the Institute of propulsion technology at DLR. The optimization presented in this paper features more than 1600 converged 3D steady-state CFD simulations at two operating conditions, takeoff and top of climb, respectively. In order to accelerate the optimization process, a surrogate model based on a Kriging interpolation on the response surfaces was introduced. The main constrains and regions of interest during the optimization were a given power split between the rotors at takeoff, retaining an axial outflow at the aft rotor exit at top of climb, and fulfilling the given thrust specifications at both operating conditions. Two objectives were defined: One was to maximize the (propeller) efficiency at top of climb conditions. The other objective was an acoustic criteria aiming at decreasing the rotor/rotor interaction noise at takeoff by smoothening the front rotor wakes. Approximately 100 geometric parameters were set free during the optimization to allow for a flexible definition of the 3D blade geometry in terms of rotor sweep, aft rotor clipping, hub contour as well as a flexible definition of different 2D profiles at different radial locations. The acoustic evaluation was carried out based on unsteady 3D-RANS computations with the same CFD method (TRACE) involving an efficient single-passage phase-lag approach. These unsteady results were coupled with the integral Ffowcs Williams-Hawkings method APSIM via a permeable control surface covering both rotors. The far field directivities and spectra for a linear microphone array were evaluated, here mainly at the takeoff certification point. This (still time consuming) acoustic evaluation was carried out after the automatic optimization for a few of the most promising individuals only, and results will be presented in comparison with the baseline configuration. This detailed acoustic evaluation also allowed for an assessment of the effectiveness of the acoustic cost function as introduced within the automatic optimization.


2018 ◽  
Vol 2018 ◽  
pp. 1-15 ◽  
Author(s):  
Yasser Mohamed Hamada

A new method based on shifted Chebyshev series of the first kind is introduced to solve stiff linear/nonlinear systems of the point kinetics equations. The total time interval is divided into equal step sizes to provide approximate solutions. The approximate solutions require determination of the series coefficients at each step. These coefficients can be determined by equating the high derivatives of the Chebyshev series with those obtained by the given system. A new recurrence relation is introduced to determine the series coefficients. A special transformation is applied on the independent variable to map the classical range of the Chebyshev series from [-1,1] to [0,h]. The method deals with the Chebyshev series as a finite difference method not as a spectral method. Stability of the method is discussed and it has proved that the method has an exponential rate of convergence. The method is applied to solve different problems of the point kinetics equations including step, ramp, and sinusoidal reactivities. Also, when the reactivity is dependent on the neutron density and step insertion with Newtonian temperature feedback reactivity and thermal hydraulics feedback are tested. Comparisons with the analytical and numerical methods confirm the validity and accuracy of the method.


Sign in / Sign up

Export Citation Format

Share Document